检索结果-南通市图书馆

Idealization Second Quantization of Composite Particles

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2001年第11期36卷 525-530页

作者： ZHOU Duan-Lu yu Si-xia SUN Chang-Pu Institute of Theoretical Physics Academia SinicaBeijing 100080China Institute of Theoretical PhysicsAcademia SinicaBeijing 100080China Institute of Theoretical PhysicsAcademia SinicaBeijing 100080China

A practical method is developed to deal with the second quantization of the many-body system containing the composite *** our treatment,the modes associated with composite particles are regarded approximately as independent ones compared with those of unbound *** field operators of the composite particles thus arise naturally in the second quantization *** be emphasized,the second quantization Hamiltonian has the regular structures which correspond clearly to different physical processes.

关键词： second quantization,composite particles

N-cadherin expression in the midbrain substantia nigra of perinatal rats

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2008年第10期3卷 1136-1140页

作者： Junping Cao yu Sun xia Du Dianshuai Gao Department of Neurobiology Xuzhou Medical College Xuzhou 221002 Jiangsu Province China

BACKGROUND： Cellular adhesion molecule mediates the effects of glial cell line-derived neurotrophic factor in dopaminergic neurons during nervous system development. It is assumed that cellular adhesion molecule plays an important role in dopaminergic neuron development. OBJECTIVE： To investigate N-cadherin expression in the midbrain substantia nigra during rat development. DESIGN, TIME AND SETTING： The developmental biology, controlled study was performed at the Laboratory of Research Center of Neurobiology, Xuzhou Medical College, China from April to October 2007. MATERIALS： Sprague Dawley rats （embryonic days 16, 18, and 20, as well as postnatal days 1, 3, 7, 14, and 21） were selected for this study. N-cadherin antibody was purchased from Santa Cruz, USA. METHODS： N-cadherin expression in the midbrain substantia nigra of perinatal rats was detected using reverse transcription polymerase chain reaction, Western blot, and immunohistochemistry methods. N-cadherin-positive cells were counted. MAIN OUTCOME MEASURES： N-cadherin mRNA, protein, and positive cells in the rat midbrain substantia nigra were quantified. RESULTS： The results of reverse transcription polymerase chain reaction and Western blot demonstrated that altered N-cadherin mRNA levels were similar to protein levels in the midbrain substantia nigra. N-cadherin mRNA and protein expression was low in the midbrain substantia nigra of embryonic day 16 rats but gradually increased, and reached a peak at postnatal day 1. N-cadherin mRNA and protein levels were still high at postnatal days 3 and 7, but significantly decreased at postnatal day 14. There was no significant difference in N-cadherin mRNA and protein expression between postnatal days 14 and 21 （P 〉 0.05）. The immunohistochemistry results demonstrated that there was no significant difference in the quantity of N-cadherin-positive cells per area in rats from embryonic day 16 to postnatal day 7 （P 〉 0.05）. The quantity of N-cadherin-positive cells per a

关键词： N-cadherin substantia nigra nervous system development

A_1 Weights and d-Homogeneous Measures on Ahlfors d-Regular Space

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2012年第5期28卷 901-908页

作者： yu xia DAI Sheng You WEN Zhi Xiong WEN Department of Mathematics Huazhong University of Science and Technology Department of Mathematics Hubei University

Let X be an Ahlfors d-regular space and rn a d-regular measure on X. We prove that a measure μ on X is d-homogeneous if and only if μ is mutually absolutely continuous with respect to m and the derivative Dmμ（x） is an A1 weight. Also, we show by an example that every Ahlfors d-regular space carries a measure which is d-homogeneous but not d-regular.

关键词： Ahlfors regular space homogeneous measure Ahlfors regular measure weight

Optimization of parental RNAi conditions for hunchback gene in Locusta migratoria manilensis （Meyen）

在线全文

学校读者我要写书评

暂无评论

Insect Science 2010年第1期17卷 1-6页

作者： Zheng-Bo He yue-Qing Cao yu-xian xia Genetic Engineering Research Center College of Bioengineering Chongqing University Chongqing Engineering Research Center for Fungal Insecticides and Key Laboratory of Functional Gene and Regulation Technologies under Chongqing Municipal Education Commission Chongqing China

An investigation on the optimization of parental RNA interference （RNAi） conditions for hunchback （hb） gene in Locusta migratoria manilensis （Meyen） was conducted. Double stranded RNA （dsRNA） corresponding to hb gene was injected into haemocoel of female adults ofL. migratoria manilensis. Embryos developed from the eggs laid by the injected adults on the 7th day after eclosion showed observable effects of RNAi for hb. The silencing effect after delivery treatment of dsRNA for hb gene was maintained for more than 21 days. A significant decrease of hb transcripts was further confirmed by Northern blot analysis. The dose of dsRNA/insect at 2μg could trigger 96.9% RNAi effects, while silencing appeared to have no dependence on the size of dsRNA. Results suggest that parental RNAi could be employed to efficiently identify the developmental gene functions in L. migratoria manilensis.

关键词： hunchback Locusta migratoria manilensis parental RNA interference

Isolation and characterization of the trehalose-6-phosphate synthase gene from Locusta migratoria manilensis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Insect Science 2009年第4期16卷 287-295页

作者： Shu-Yan Cui yu-xian xia 2008-09-16 School of Bioengineering Chongqing University Chongqing Engineering Research Center for Fungal Insecticide The Key Laboratory of Gene Function and Expression Regulation Chongqing China

Trehalose plays an important role in protecting organisms from various stresses. Trehalose-6-phosphate synthase （TPS） is the key enzyme in trehalose synthesis, but in insects only a few TPS genes have been identified and their function has not been well characterized. To better understand the function of TPS in insects, a complete TPS complementary DNA （eDNA） clone was obtained from the fat body of the locust Locusta migratoria manilensis （GenBank accession number： EU131894）. The full-length cDNA is 2 806 bp, including an open reading frame of 2 442 bp, which encodes an 813 amino acids protein with a calculated molecular weight of 91 976 Daltons and an isoelectric point of 6.14. The deduced amino acid sequence is highly similar to other published insect TPS and its C-terminal also has a region homologous to trehalose phosphate phsophatase （TPP）. Semi-quantitative analysis indicated that the TPS transcript was expressed not only in fat body, but also in gut, hemolymph and leg muscle. These data may facilitate studies of TPS function in insects and improve our understanding of trehalose metabolism.

关键词： cloning Locusta migratoria-manilensis trehalose-6-phosphate synthase,RT-PCR

Host-guest interaction tailored cucurbit[6]uril-based supramolecular organic frameworks(SOFs) for drug delivery

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2022年第3期33卷 1529-1532页

作者： Chun Liu yu xia Zhu Tao Xin-Long Ni Key Laboratory of Macrocyclic and Supramolecular Chemistry of Guizhou Province Guizhou UniversityGuiyang 550025China College of Chemistry and Chemical Engineering Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan ProvinceHunan Normal UniversityChangsha 410081China

An approach for the construction of crystalline porous supramolecular organic frameworks (SOFs) via outer-surface interactions of cucurbit[6]uril (Q[6]) with high yield is presented. This approach enables the noncovalent integration of guest molecules into ordered topologies and creates new host-guest-complex-based SOFs;i.e., the topology can be predesigned and constructed by using [ZnCl_(4)]^(2-) anions to induce the formation of solid Q[6]-SOFs, and the pore wall surface can be easily modified by the Q[6]-encapsulated guest molecules. In addition, one of prepared solid Q[6]-SOFs showed a high drug-loading capacity and smart potential release control for drug-delivery applications.

关键词： Cucurbituril SOFs Porous materials Host-guest interaction Drug delievery

Carbon emission impact on the operation of virtual power plant with combined heat and power system

在线全文

学校读者我要写书评

暂无评论

Frontiers of Information Technology & Electronic Engineering 2016年第5期17卷 479-488页

作者： yu-hang xia Jun-yong LIU Zheng-wen HUANG Xu ZHANG School of Electrical Engineering and Information Sichuan UniversityChengdu 610065China Brunel Institute of Power Systems Brunel UniversityLondon UB8 3PHUK Guangzhou Power Supply Bureau Guangzhou 510000China

A virtual power plant （VPP） can realize the aggregation of distributed generation in a certain region, and represent distributed generation to participate in the power market of the main grid. With the expansion of VPPs and ever-growing heat demand of consumers, managing the effect of fluctuations in the amount of available renewable resources on the operation of VPPs and maintaining an economical supply of electric power and heat energy to users have been important issues. This paper proposes the allocation of an electric boiler to realize wind power directly converted for supplying heat, which can not only overcome the limitation of beat output from a combined heat and power （CHP） unit, but also reduce carbon emissions from a VPP. After the electric boiler is considered in the VPP operation model of the combined heat and power system, a multi-objective model is built, which includes the costs of carbon emissions, total operation of the VPP and the electricity traded between the VPP and the main grid. The model is solved by the CPLEX package using the fuzzy membership function in Matlab, and a case study is presented. The power output of each unit in the case study is analyzed under four scenarios. The results show that after carbon emission is taken into account, the output of low carbon units is significantly increased, and the allocation of an electric boiler can facilitate the maximum absorption of renewable energy, which also reduces carbon emissions from the VPP.

关键词： Virtual power plant (VPP) Carbon emissions Electric boiler Wind power Combined heat and power (CHP)

Optimized shearing strategy for heavy plate based on contour recognition

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2023年第9期30卷 1821-1833页

作者： Jian-zhao Cao yu-xia Wang Shao-wen Huang Chang-tao Wang School of Computer Science and Engineering Shenyang Jianzhu UniversityShenyang 110168LiaoningChina Shandong Iron and Steel Co. Ltd.Jinan 271105ShandongChina School of Electrical and Control Engineering Shenyang Jianzhu UniversityShenyang 110168LiaoningChina

The shearing line is the key to improve the quality and efficiency of heavy plates.A model of contour recognition and intelligent shearing strategy for the heavy plate was ***,multi-array binocular vision linear cameras were used to complete the image ***,the total length of the steel plate after cooling was predicted by back propagation neural network algorithm according to the contour ***,using the scanning line and a new camber description method,the shearing strategy including head/tail irregular shape length and rough dividing strategy was *** practical application shows that the model and strategy can effectively solve the problems existing in the shearing process and can effectively improve the yield of steel *** maximum error of detection width,length,camber,and the length of the irregular deformation area at the head/tail of the plate are all less than 5 *** correlation coefficient of the length prediction model based on the back propagation neural network is very *** reverse ratio result of edge cutting failure using the proposed rough dividing strategy is 1/401=0.2%,which is 2%higher than that by human.

关键词： Heavy plate Contour detection Intelligent shearing strategy Length prediction Neural network model

Bright compact ultrabroadband source by orthogonal laser-sustained plasma

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Light(Science & Applications) 2024年第11期13卷 2756-2766页

作者： Zhaojiang Shi Shichao Yang He Hu Haodong Lei Zhaohua Yang xia yu School of Instrumentation and Optoelectronic Engineering Beihang UniversityBeijing 100191China

Laser-sustained plasma(LSP)source featuring high brightness and broadband spectral coverage is found to be powerful in various fields of scientific and industrial ***,the fundamental limit of low conversion efficiency constrains the system compactness and widespread applications of such broadband light *** this paper,we propose an innovative orthogonal LSP to break through the conversion efficiency *** by the elevated conversion efficiency from absorbed laser power to ultraviolet(UV)emission,a compact broadband source(250–1650 nm)with UV spectral radiance exceeding 210 mW=emm2·sr·nmT is achieved with>100W pump *** the plot of a two-dimensional refractive index model,we report an important conceptual advance that the orthogonal design eliminates the influence of the negative lensing effect on laser power *** results unambiguously demonstrate that we achieve a bright compact UV-VIS-NIR source with negligible thermal loss and the highest conversion efficiency to our *** enhancement of 4 dB contrast-to-noise ratio(CNR)in spectral single-pixel imaging has been demonstrated using the proposed ultrabroadband *** establishing the quantitative link between pumping optics design and plasma absorption,this work presents a compact broadband source that combines superior conversion efficiency and unprecedented brightness,which is essential to high-speed inspection and spectroscopy applications.

关键词： source orthogonal sustained