检索结果-南通市图书馆

同方期刊数据库

在线全文

学校读者我要写书评

暂无评论

量子核判别分析算法

郑州大学学报（理学版） 2025年第1期57卷 61-66页

作者：康榕乘余凯张新林崧郭躬德福建师范大学计算机与网络空间安全学院福建福州350117 福建师范大学数字福建环境监测物联网实验室福建福州350117 福建师范大学数学与统计学院福建福州350117

核判别分析法通过核函数扩展了线性判别分析对非线性数据的处理能力,成为模式识别领域中一个重要的分支。然而,随着数据的指数增长,经典核判别分析算法在提取特征时会消耗大量计算资源。针对这一问题,利用量子叠加性和并行性提出了一种... 详细信息

核判别分析法通过核函数扩展了线性判别分析对非线性数据的处理能力,成为模式识别领域中一个重要的分支。然而,随着数据的指数增长,经典核判别分析算法在提取特征时会消耗大量计算资源。针对这一问题,利用量子叠加性和并行性提出了一种量子核判别分析算法。首先,借助量子随机存储器技术与控制旋转操作构造需要的类间矩阵和类内矩阵所对应的密度算子;然后,融入线性方程的求解思路并行获取特征态。理论分析表明,所提算法与经典算法相比具有指数级加速。

关键词：量子机器学习非线性判别分析核函数特征提取量子厄米特链积相位估计

同方期刊数据库博看期刊

Gradient estimates and coupling property for semilinear SDEs driven by jump processes

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2015年第2期58卷 447-458页

作者： song Yu lin School of Mathematical Sciences Beijing Normal University

Let L be a L′evy process with characteristic measureν,which has an absolutely continuous lower bound *** Lebesgue measure on *** using Malliavin calculus for jump processes,we investigate Bismut formula,gradient est... 详细信息

关键词： jump processes Bismut formula gradient estimates coupling property

Influence of Water Vapor on Silica Membrane： Adsorption Properties and Percolation Effect

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Physics 2015年第3期28卷 345-350,I0002页

作者： Chun-lin song Gang Liu Faculty of Materials and Energy Southwest University Chongqing 400715 China Inorganic Membrane Group MESA+ Institute for Nanotechnology Faculty of Science and Technology University of Twente P.O. Box 217 7500 AE Enschede the Netherlands

The influence of water vapor on silica membrane with pore size of ,-4A has been investigated in terms of adsorption properties and percolation effect at 50 and 90 ℃. Two methods are employed： spectroscopic ellipsometry for water vapor adsorption and gas permeation of binary mixture of helium and H2O The adsorption behaviors on the silica membrane comply with the first-order Langmuir isotherm. The investigation demonstrates that helium flux through the silica membrane decreases dramatically in presence of H20 molecules. The transport of gas molecules through such small pores is believed not to be continuous any more, whereas it is reasonably assumed that the gas molecules hop from one occupied site to another unoccupied one under the potential gradient. When the coverage of H20 molecules on the silica surface increases, the dramatic decrease of helium flux could be related to percolation effect, where the adsorbed H20 molecules on the silica surface block the hopping of helium molecules.

关键词： Silica membrane Percolation effect Adsorption

Perovskite solar cells toward industrialization: Screen printed perovskite films

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

Materials Reports(Energy) 2022年第4期2卷 1-2页

作者： lin song Frontiers Science Center for Flexible Electronics(FSCFE) Institute of Flexible ElectronicsNorthwestern Polytechnical UniversityXi'an710072PR China

Perovskite solar cells(PSCs)have reached a recorded power conversion efficiency(PCE)of 25.7%just over a decade.1 Due to the solution processability,various deposition methods have been developed to prepare PSCs,including spin coating,blade coating,spray coating,slot-die printing,and ink-jet printing.2,3 Among them,screen printing has received great attention due to the unique advantages of customized pattern design,high throughput,and low-cost *** this technology holds a great promise for industrialization of perovskite solar cells.4 Till now,screen printing has been successfully applied to prepare buffer layers and electrodes of PSCs,but attempts in perovskite-layer fabrication have *** key problem is that the commonly used organic solvents with a low viscosity are not fit for screen printing,which limits the application of this deposition technology for perovskite-film manufacturing.

关键词： coating printing Screen

Synthesis and Structural Characterization of a New Hydrogen-bonded Polyrotaxane of [Co(H_2O)_6]_(2+) with 1,1′-(Propane-1,3-diyl)dipyridinium-4-carboxylate

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

Chinese Journal of Structural Chemistry 2006年第8期25卷 957-964页

作者： JIANG Ning-Yi LI song-lin Department of Chemistry College of Science Tianjin University Tianjin 300072 China

A new double betaine 1,1′-（propane-1,3-diyl）dipyridinium-4-carboxylate L has been synthesized. Reaction of 1, 1′-（propane-1,3-diyl）dipyridinium-4-carboxylate tetrahydrate 1 with Co（ClO4）2-6H2O leads to the formation of a new Co（Ⅱ） coordination compound, namely [Co（H2O）6]-2H2O-2L-2ClO4 2. The crystal structures of 1 and 2 have been determined by single-crystal X-ray diffraction method. Crystal data for 1. monoclinic, space group C2/c, a = 18.945（4）, b = 7.700（2）, c = l 1.888（2）A,β = 101.67（3）°, V = 1698.3（6） A^3, Z = 4, F（000） = 760.0, Dc = 1.402 g/cm^3, the final R = 0.0607 and wR = 0.1607 for 950 observed reflections （1 〉 2σ（I））; and those for 2： monoclinic, space group P21/c, a = 17.982（1）, b = 15.879 （1）, c = 7.0716（5）/A,β= 100.675（1）°, V= 1984.3（3） ,A^3 Z= 4, F（000） = 1010.0, Dc = 1.631 g/cm^3, the final R = 0.0316 and wR = 0.0896 for 3784 observed reflections （1 〉20（I））. Crystal structure analysis indicates that in 1, molecules of L in a ＂V-shaped＂ conformation are linked to chains sustained by O-H…O hydrogen bonds between carboxylate groups and solvent water molecules. The chains are joined by O-H…O and C-H…O hydrogen bonds to further expand into a three-dimensional structure. For 2, molecules of L in a ＂Z-shaped＂ conformation are linked by hydrogen bonds between carboxylate groups and aqua ligands to form a chain of loops running down the b axis. The （2D→2D） polythreading in compound 2 represents the mode of parallel interpenetration of 2D sheets, having polyrotaxane character.

关键词： 1,1′-(propane-1,3-diyl)dipyridinium-4-carboxylate polyrotaxane hydrogen bonding betaine derivative

Sludge reduction with Tubificidae and the impact on the performance of the wastewater treatment process

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2007年第3期19卷 257-263页

作者： GUO Xue-song LIU Jun-xin WEI Yuan-song LI lin Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

To reduce excess sludge, a Tubificidae reactor was combined with an integrated oxidation ditch with vertical circle （IODVC）, and a new integrated system was developed for wastewater treatment, A pilot-scale of this integrated system was tested to investigate the sludge reduction with Tubificidae and the impact on effluent quality and sludge production. The dominant worm was Branchnria Sowerbyi in the Tubificidae reactor after inoculation of Branchnria Sowerbyi and Limnodrilns sp., and the maximal volume density of wet Tubificidae in vessels of the Tubificidae reactor was 17600 g/m^3. Two operational modes, treating the excess sludge （first mode） and the returned sludge （second mode） of IODVC by the Tubificidae reactor, were used in this experiment. The results showed that the excess sludge reduction rate was 46.4% in the first mode, and the average sludge yield of the integrated system was 6.19× 10^-5 kg SS/kg COD in the second mode. Though the sludge returned to IODVC via the Tubificidae reactor, it had little impact on the effluent quality and the sludge characteristics of the IODVC. No new type of recalcitrant substance in the supernatant was discharged into the environment when the sludge was treated by Tubificidae. The experimental results also indicated that no significant changes occurred on the viscosity, specific resistance, and the floc size distribution of the sludge.

关键词： integrated wastewater treatment system sludge reduction wastewater treatment Tubificidae

Mechanism for acetic acid-catalyzed ester aminolysis

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2018年第8期29卷 1233-1236页

作者： Chang Xiao song-lin Zhang Key Laboratory of Synthetic and Biological Colloids Ministry of Education School of Chemical and Material Engineering Jiangnan University

This paper reports a computational study elucidating reaction mechanism for amide bond formation from esters and amines catalyzed by acetic acid. Two optional mechanisms（namely, classic stepwise and concerted acyl substitution mechanisms） have been studied. Calculation results establish the reaction energy profiles of both mechanisms and locate all the intermediates and transition states in both catalytic cycles. Our results propose that the concerted acyl substitution mechanism may be more likely wherein the formation of CààN bond and the cleavage of CààO bond occur concurrently without the need of rehybridization of the carbonyl carbon. This is also consistent with the fact that no significant racemization/epimerization were observed in the amide products when asymmetric esters and/or amines were used as the reactants, because concerted acyl substitution mechanism precludes the intermediacy of tetrahedral adducts and the accompanying generation/elimination of new chiral *** discussion implies that the concerted acyl substitution mechanism may widely occur in related amidation reactions in the presence of different types of coupling reagents.

关键词： Amide bond formation Aminolysis Mechanism Ester Concerted acyl substitution Acid catalyzed amidation

Arbitrated quantum signature scheme based on reusable key

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2014年第11期57卷 2079-2085页

作者： YU ChaoHua GUO GongDe lin song School of Mathematics and Computer Science Fujian Normal University Key Lab of Network Security and Cryptography Fujian Normal University

An arbitrated quantum signature scheme without using entangled states is *** the scheme,by employing a classical hash function and random numbers,the secret keys of signer and receiver can be *** is shown that the proposed scheme is secure against several well-known ***,it can stand against the receiver’s disavowal ***,compared with previous relevant arbitrated quantum signature schemes,the scheme proposed has the advantage of less transmission complexity.

关键词： signature signer receiver secret message cryptography encryption entangled reused resist

New insights into the regulation of Axin function in canonical Wnt signaling pathway

在线全文

学校读者我要写书评

暂无评论

Protein & Cell 2014年第3期5卷 186-193页

作者： Xiaomin song Sheng Wang lin Li State Key Laboratory of Molecular Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for BiologicalSciences Chinese Academy of Sciences Shanghai 200031 China

The Wnt signaling pathway plays crucial roles during embryonic development, whose aberration is implicated in a variety of human cancers. Axin, a key component of canonical Wnt pathway, plays dual roles in modulat- ing Wnt signaling： on one hand, Axin scaffolds the ＂l^-catenin destruction complex＂ to promote 13-catenin degradation and therefore inhibits the Wnt signal transduction; on the other hand, Axin interacts with LRP5/6 and facilitates the recruitment of GSK3 to the plasma membrane to promote LRP516 phosphorylation and Wnt signaling. The differential assemblies of Axin with these two distinct complexes have to be tightly controlled for appropriate transduction of the ＂on＂ or ＂off＂ Wnt signal. So far, there are multiple mechanisms revealed in the regulation of Axin activity, such as post- transcriptional modulation, homo/hetero-polymerization and auto-inhibition. These mechanisms may work cooperatively to modulate the function of Axin, thereby playing an important role in controlling the canonical Wnt signaling. In this review, we will focus on the recent progresses regarding the regulation of Axin function in canonical Wnt signaling.

关键词： Wnt signaling Axin post-transcriptionalmodification polymerization auto-inhibition