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Photo-induced deep aerobic oxidation of alkyl aromatics

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Science China Chemistry 2021年第9期64卷 1487-1492页

作者： Chang-Cheng Wang guo-xiang zhang Zhi-Wei Zuo Rong Zeng Dan-Dan Zhai Feng Liu zhang-Jie Shi Department of Chemistry Fudan UniversityShanghai200438China Department of Chemistry Xi’an Jiaotong UniversityXi’an710049China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryShanghai200032China

Oxidation is a major chemical process to produce oxygenated chemicals in both nature and the chemical ***,the industrial manufacture of benzoic acids and benzene polycarboxylic acids(BPCAs)is mainly based on the deep oxidation of polyalkyl benzene,which is somewhat suffering from environmental and economical disadvantage due to the formation of ozone-depleting Me Br and corrosion hazards of production *** this report,photo-induced deep aerobic oxidation of(poly)alkyl benzene to benzene(poly)carboxylic acids was ***_(3) was proved to be an efficient HAT(hydrogen atom transfer)catalyst in the presence of alcohol as both hydrogen and electron ***(O_(2))was found as a sole terminal *** most cases,pure products were easily isolated by simple filtration,implying large-scale implementation *** reaction provides an ideal protocol to produce valuable fine chemicals from naturally abundant petroleum feedstocks.

关键词： photo-induced oxidation alkyl aromatics

Nonlinear dynamics of angle-ply composite laminated thin plate with third-order shear deformation

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Science China(Technological Sciences) 2010年第3期53卷 612-622页

作者： guo xiang Ying,zhang Wei & YAO MingHui College of Mechanical Engineering,Beijing University of Technology,Beijing 100124,China 1. College of Mechanical Engineering Beijing University of Technology Beijing 100124 China

An asymptotic perturbation method is presented based on the Fourier expansion and temporal rescaling to investigate the nonlinear oscillations and chaotic dynamics of a simply supported angle-ply composite laminated rectangular thin plate with parametric and external *** to the Reddy's third-order plate theory,the governing equations of motion for the angle-ply composite laminated rectangular thin plate are derived by using the Hamilton's ***,the Galerkin procedure is applied to the partial differential governing equation to obtain a two-degrees-of-freedom nonlinear system including the quadratic and cubic nonlinear *** equations are utilized to deal with the resonant case of 1:1 internal resonance and primary parametric resonance-1/2 subharmonic ***,the stability analysis is given for the steady-state solutions of the averaged *** on the averaged equation obtained by the asymptotic perturbation method,the phase portrait and power spectrum are used to analyze the multi-pulse chaotic motions of the angle-ply composite laminated rectangular thin *** certain conditions the various chaotic motions of the angle-ply composite laminated rectangular thin plate are found.

关键词： angle-ply composite laminated plate third-order shear deformation theory parametric excitation chaotic motion

Genetic Effect on Yield and Fiber Quality Traits of 16 Chromosome Substitution Lines in Upland Cotton

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Agricultural Sciences in China 2008年第11期7卷 1290-1297页

作者： LUAN Ming-bao guo xiang-mo zhang Yong-shan YAO Jin-bo Key Laboratory of Cotton Germplasm Improvement Ministey of Agriculture/Cotton Research Institute Chinese Academy of Agricultural Sciences （ CAAS） A ny ang 455000 P.R. Ch ina

Evaluation of the genetic effect on yield and fiber quality can provide useful information on cotton breeding. Sixteen CSB lines and TM-1 introduced from USDA/ARS were used as male and top-crossed with three elite cultivars and the 51 F1 hybrids, 16 CSB lines, TM-1, and 3 elite cultivars were planted at the Cotton Research Institute of CAAS, Anyang, Henan Province and Xiajin, Shandong Province, China. The yield traits and fiber quality data were obtained and additive and dominance effect on each trait were measured by AD model. Boll weight takes the largest additive proration, whereas boll number takes the least additive proration. The largest and the least dominant proration for lint yield and boll weight were measured, respectively. Fiber length has the additive and dominance effect, and dominance effect was slightly more than additive effect. Larger additive and no dominance effect on uniformity, micronaire, and fiber strength were measured. Significantly, positive additive effect on boll weight of CSB06 and CSB12Sh was observed. CSB14Sh and CSB01 have significantly positive additive effect on 4 and 3 traits of fiber quality, respectively. CSB01 has the greatest dominant effect on lint yield among CSB lines. The dominant effect on fiber length of CSB lines showed positive. It is beneficial to use CSB06 and CSB12Sh as parents to improve boll size, to use CSB14Sh and CSB01 as parents to improve fiber quality. As for hybrid cotton breeding, it is reasonable using CSB01 to improve lint yield traits, and using CSB01, CSB11Sh, and CSB06 to improve fiber length.

关键词： chromosome substitution lines in upland cotton additive genetic effect dominance genetic effect AD model

NUMERICAL AND EXPERIMENTAL STUDY ON LIQUID-SOLID FLOW IN A HYDROCYCLONE

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Journal of Hydrodynamics 2009年第3期21卷 408-414页

作者： WANG Li-yang ZHENG Zhi-chu WU Ying-xiang guo Jun zhang Jun TANG Chi Laboratory of Applied Fluid Dynamics Division of Engineering Sciences Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China

Hydrocyclones are widely used in industry, of which the geometrical design using CFD techniques is gaining more popularity in recent years. In this study, the Euler-Euler approach and the Reynolds stress model are applied to simulate the liquid-solid flowfield in a hydrocyclone. The methodology is validated by a good agreement between experimental data and numerical results. Within the research range, the simulation indicates that the liquid-solid separation mainly occurs in the conical segment, and increasing conical height or decreasing cylindrical height helps to improve the grade efficiencies of solid particles. Based on these results, two of the same hydrocyclones are designed and installed in series to establish a liquid-solid separation system. Many experiments are then conducted under different conditions, in which the effects of the water cut and the second hydrocyclone on the separation are investigated. The results also confirm that smaller solid particles are more susceptible to the inlet conditions, and the second hydrocyclone plays a more important role as the water cut reduces.

关键词： hydrocyclone liquid-solid flow model efficiency

Effects of Limiting Amino Acids on Rumen Fermentation and Microbial Community In vitro

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Agricultural Sciences in China 2008年第12期7卷 1524-1531页

作者： WANG Meng-zhi WANG Hong-rong CAO Heng-chun LI guo-xiang zhang Jie College of Animal Science and Technology Yangzhou University Yangzhou 225009 P.R.China

Three goats fitted with cannula were used to provide rumen liquor to investigate the effects of limiting amino acids on rumen fermentation and microbial community in vitro. The removal method was used in the current experiments. Treatments are total essential amino acid （TEAA）, His-removal, Lys-removal, Met-removal, and branch chain amino acid （BCAA）- removal. Results indicated that, pH-value ranged between 5.9 and 6.8, with the highest mean value for the group with BCAA-removal （6.54） in the culture. Concentration of NH3-N ranged between 10.99 to 30.51 mg 100 mL^-1, with the group of TEAA recording the highest average NH3-N concentration （17.85 mg 100 mL^-1）. Yields of microbial protein and limiting degree on microbial growth varied with treatments （P 〈 0.01）, and the lowest accrued in treatment with BCAA-removal （0.1389, 0.1772, and 0.3161 mg mL^-1 for bacteria, protozoa, and mixed microbes, respectively）, compared to the group with TEAA, microbial production of mixed microbes decreased by 44.52%. As for micro-flora, protozoa to bacteria ratio was the lowest for the group with Lys-removal （89.12%）, while the highest for the group with BCAA-removal （127.60%）（P 〈 0.01）. Furthermore, PCR-SSCP analysis revealed that, microbial profile subjected to substrates within bacteria and protozoa groups. It was therefore concluded that, dietary amino acid influenced both rumen fermentation and microbial characteristics.

关键词： limiting amino acids rumen microbes limiting degree,

Reduced-glutathione concentrations in Boleophthalmus pectinirostris tissues exposed to benzo(a)pyrene

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Journal of Environmental Sciences 2001年第3期13卷 308-310页

作者： FENG Tao 1, ZHENG Wei yun 1, guo xiang\|qun\+2, zhang Yong\+1(1.Environmental Science Research Center, Xiamen University, Xiamen 361005, China 2.Chemistry Department, Xiamen University, Xiamen\ 361005, China) Environmental Science Research Center Xiamen University Xiamen 361005 China.

The concentrations of reduced-glutathione ( GSH) in liver and ovary of Boleophthalmus pectinirostris are quantified. The concentrations of GSH in the ovary are much higher than that of GSH in the liver(nearly 3 times of the liver). The study also investigates the changes of GSH contents in the two organs while the fishes were exposed to benzo(a)pyrene(BaP) at concentrations of 0, 0.05, 0.2 and 0.5 mg/L respectively for up to a week. The concentrations of GSH in the liver of BaP-exposed fish increased significantly with dose, whereas the concentrations of GSH in the ovary decreased significantly compared to controls. The results suggested that both the liver and the ovary are the primary organ in BaP metabolism, and that the changes of GSH levels may represent an adaptive response or toxic effect to Bap exposure.

关键词： Boleophthalmus pectinirostris benzo(a)pyrene reduced-glutathione

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便携式上转换荧光试纸条检测仪的研制

光学精密工程 2017年第3期25卷 584-590页

作者：董国亚赵翔张燕孙传强河北工业大学电气工程学院天津300401 天津科技大学食品工程与生物技术学院天津300457 天津大学精密仪器与光电子工程学院天津300072

为了实现对上转换荧光试纸条的定量检测,研制了便携式上转换荧光试纸条检测仪,并通过实际测试验证了仪器的主要性能。首先,介绍了上转换荧光技术以及上转换荧光试纸条的测试原理,描述了以光学扫描检测系统和电路系统为核心的便携式荧光... 详细信息

为了实现对上转换荧光试纸条的定量检测,研制了便携式上转换荧光试纸条检测仪,并通过实际测试验证了仪器的主要性能。首先,介绍了上转换荧光技术以及上转换荧光试纸条的测试原理,描述了以光学扫描检测系统和电路系统为核心的便携式荧光试纸条检测仪的设计方案,能够将试纸条的荧光信号转变为电信号并进行处理;然后,基于设计方案研制了检测仪样机,并对实际检测试纸条采集到的信号进行优化;最后,对检测仪的性能进行了测试。测试结果表明:仪器稳定、重复性好,样本检测标准差小于0.004;线性响应特性良好,拟合出的浓度标准曲线决定系数为0.996 3。该检测仪结构精巧、功耗低、性能良好,很好地满足了上转换荧光试纸条定量检测的需求。

关键词：上转换荧光技术光学扫描标准曲线拟合定量检测低功耗

一类含有界随机参数经济系统的Hopf分岔分析

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统计与决策 2017年第21期33卷 15-18页

作者：郭祥马少娟张莉莉北方民族大学数学与信息科学学院银川750021

文章应用Chebyshev正交多项式逼近法研究了一类含有界随机参数经济系统的Hopf分岔现象,随机系统首先被转化成等价的确定性系统,并得到系统发生Hopf分岔的条件,然后通过数值仿真验证了理论结果。仿真结果表明:受随机因素的影响,系统具有... 详细信息

文章应用Chebyshev正交多项式逼近法研究了一类含有界随机参数经济系统的Hopf分岔现象,随机系统首先被转化成等价的确定性系统,并得到系统发生Hopf分岔的条件,然后通过数值仿真验证了理论结果。仿真结果表明:受随机因素的影响,系统具有复杂的非线性动力学特性,并得出参数随机强度δ逐渐增大时不仅会使系统分岔参数值左移而且会抑制极限环幅值的增大。

关键词：经济系统 Hopf分岔 Chebyshev多项式

ImSpiRE: image feature-aided spatial resolution enhancement method

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Science China Life Sciences 2025年第1期 272-283页

作者： Yuwei Hua Yizhi zhang Zhenming guo Shan Bian Yong zhang State Key Laboratory of Cardiovascular Diseases and Medical Innovation Center Institute for Regenerative MedicineDepartment of NeurosurgeryShanghai East HospitalShanghai Key Laboratory of Signaling and Disease ResearchFrontier Science Center for Stem Cell ResearchSchool of Life Sciences and TechnologyTongji University

The resolution of most spatially resolved transcriptomic technologies usually cannot attain the single-cell level, limiting their applications in biological discoveries. Here, we introduce ImSpiRE, an image feature-aided spatial resolution enhancement method for in situ capturing spatial transcriptome. Taking the information stored in histological images, ImSpiRE solves an optimal transport problem to redistribute the expression profiles of spots to construct new transcriptional profiles with enhanced resolution, together with extending the gene expression profiles into unmeasured regions. Applications to multiple datasets confirm that ImSpiRE can enhance spatial resolution to the subspot level while contributing to the discovery of tissue domains, signaling communication patterns, and spatiotemporal characterization.

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