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On Periodic Oscillation and Its Period of a Circadian Rhythm Model

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Communications on Applied Mathematics and Computation 2022年第3期4卷 1131-1157页

作者： Miao Feng Chen Zhang department of Mathematics Shanghai Normal UniversityShanghai 200234China

We theoretically study periodic oscillation and its period of a circadian rhythm model of Neurospora and provide the conditions for the existence of such a periodic oscillation by the theory of competitive dynamical *** present the exact expression of the unique equilibrium in terms of parameters of system,we divide them into eleven classes for the Hill coefficient n=1 or n=2,among seven classes of which nontrivial periodic oscillations *** simulations are made among the seven classes and the models with the Hill coefficient n=3 or n=4 to reveal the influence of parameter variation on periodic oscillations and their *** results show that their periods of the periodic oscillations are approximately 21.5 h,which coincides with the known experiment result observed in constant darkness.

关键词： Rhythm model Km-type competition system Periodic oscillation Period

Correlation of final state Interaction with the Detection Phase Space

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Chinese Physics Letters 1998年第2期15卷 86-88页

作者： YANG Chun CHEN Tao YE Yan-lin YING Jun XU Chun-cheng LIU Hong-tao department of Technical Physics and Institute of Heavy Ion Physics Peking UniversityBeijing 100871

The final state interaction between the emitting particles has been expected to play an important role to discriminate the signal and background channels in the experiment which detects low mass *** this effect is shown most clearly in the invariant mass spectrum which display a narrow peak for the dibaryon decaying particles and a flat distribution for the background *** our detailed simulation study indicates that the detection phase space will largely change the shape of the *** calculation for TRIUMF-E772,which is designed to search for d^(*) dibaryon,shows that the spectra of signal and background become similar to each other and therefore the discrimination is certainly ineffective.

关键词： particles. spectra. state

Forward heuristic breadth-first reasoning based on rule match for biomass hybrid soft-sensor modeling in fermentation process

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Journal of Beijing Institute of Technology 2012年第1期21卷 128-133页

作者：安莉王建林 department of Information Science and Technology Beijing University of Chemical Technology

Biomass is a key parameter in fermentation process, directly influencing the performance of the fermentation system as well as the quality and yield of the targeted product. Hybrid soft-sensor modeling is a good method for on-line estimation of biomass. Structure of hybrid soft-sensor model is a key to improve the estimating accuracy. In this paper, a forward heuristic breadth-first reasoning approach based on rule match is proposed for constructing structure of hybrid model. First, strategy of forward heuristic reasoning about facts is introduced, which can reason complex hybrid model structure in the event of few known facts. Second, rule match degree is defined to obtain higher esti- mating accuracy. The experiment results of Nosiheptide fermentation process show that the hybrid modeling process can estimate biomass with higher accuracy by adding transcendental knowledge and partial mechanism to the process.

关键词： fermentation process biomass soft-sensor modeling rule match

experimentAL RESEARCH ON RADIATION FROM DOUBLE CYLINDRICAL STRUCTURES

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Journal of Hydrodynamics 2006年第2期18卷 156-160页

作者： JI Gang ZHANG Wei-kang ZHOU Qi-dou department of Naval Architecture and Ocean Engineering Naval University of Engineering Wuhan 430033China

An experiment on radiation from double cylindrical structures was held in an open-air pond. Radiation responses from one-point harmonic force driven model and two-point stochastic forces driven model were measured. Nu... 详细信息

关键词： acoustic radiation experiment double cylindrical structure

Phytopharmacological evaluation of ethanol extract of Sida cordifolia ***

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Asian Pacific Journal of Tropical Biomedicine 2014年第1期4卷 18-24页

作者： Mohammad Abdul Motalib Momin Sm Faysal Bellah Sarder Mohammad Raussel Rahman Ahmed Ayedur Rahman Gazi Mohammad Monjur Murshid Sarder Mohammad Saker Billah Talha Bin Emran department of Pharmacy Jahangirnagar University department of Clinical Pharmacy and Pharmacology Dhaka University Pharmacy Discipline Life Science SchoolKhulna University department of Chemistry Gort.M.M.University College department of Pharmacy BGC Trust University

Objective:To investigate the phytochemical screening(group determination)and selected pharmacological activities(antioxidant,antimicrobial and analgesic activity)of the plant Sida cordifolia Linn(***).Methods:Eighty percent concentrated ethanol extract of the roots was *** identify the chemical constituents of plant extract standard procedures were *** phytochemical screening the crude extract was tested for the presence of different chemical groups like reducing sugar,tannins,saponins,steroids,flavonoids,gums,alkaloids and *** antioxidant property of ethanolic extract of *** was assessed by DPPH free radical scavenging *** activity of the extract was tested using the model of acetic acid induced writhing in *** sodium is used as reference standard drug for the analgesic activity test Antibacterial activity of plant extract was carried out using disc diffusion method with five pathogenic bacteria comparison with kanamycin as a ***:Phytochemical analysis of the ethanolic extract of the roots of *** indicated the presence of reducing sugar,alkaloids,steroids and *** DPPH scavenging assay the IC_(50)value was found to be 50 ug/mL which was not comparable to the standard ascorbic *** crude extract produced 44.3%inhibition of writhing at the dose of 300 mg/kg body weight which is statistically significant(P>0.001).The in vitro antimicrobial activity of the ethanol extract of the roots of *** showed no antimicrobial activity against five types of *** experiment was conducted only with five species of bacteria as test species,which do not at all indicate the total inactivity against ***:The obtained results provide a support for the use of this plant in traditional medicine but further pharmacological studies are required.

关键词： Antioxidant Antimicrobial Analgesic DPPH Phytochemical screening

A Hand-Eye Vision Measuring System for Articulate Robots

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Tsinghua Science and Technology 2004年第3期9卷 356-362页

作者：岁波都东陈强韩翔宇王力张骅 department of Mechanical Engineering Tsinghua University Beijing 100084 China

To make dynamic measurements for an articulate robot, a hand-eye vision measuring system is built up. This system uses two charge coupled device (CCD) cameras mounted on the end-effector of the robot. System analysis is based on the stereovision theory and line-matching technology, using a computer to evaluate the dynamic performance parameters of an articulate robot from the two images captured by the two cameras. The measuring procedure includes four stages, namely, calibration, sampling, image process-ing, and calculation. The path accuracy of an articulate industrial robot was measured by this system. The results show that this system is a low-cost, easy to operate, and simple system for the dynamic performance testing of articulate robots.

关键词： hand-eye vision measuring system path accuracy articulate robot

Volatilization of zinc and lead in direct recycling of stainless steel making dust

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中国有色金属学会会刊：英文版 2004年第2期14卷 392-396页

作者：彭及彭兵余笛唐谟堂 J.Lobel J.A.Kozinski School of Metallurgical Science and Engineering School of Information Science and Engineering department of Metallurgical Engineering

The volatilization of zinc and lead from the stainless steel making dust pellets in the direct recycling procedure was conducted by using a thermo-gravimetric analyzer and a Tamman furnace in the nitrogen atmosphere respectively. The results show that the temperature has a significant effect on the volatilization rates of zinc and lead, and the carbon content in the pellets has no effect on the volatilization process. The volatilization of zinc is controlled by the chemical reaction between zinc oxide and carbon monoxide, while the volatilization of lead is controlled by the evaporation from liquid phase to the atmosphere. The volatilization of zinc and lead mainly happen at about 1 000 ℃ according to non-isothermal experiment.

关键词：不锈钢炼钢冶炼烟尘电弧炉 AOD炉 VOD炉

Apoptosis of A549 cells by small interfering RNA targeting survivin delivery using poly-β-amino ester/guanidinylated O-carboxymethyl chitosan nanoparticles

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Asian Journal of Pharmaceutical Sciences 2020年第1期15卷 121-128页

作者： Yue Tang Yun Liu Yuwen Xie Jing Chen Yushun Dou department of Pharmacy China Pharmaceutical UniversityNanjing 211198China

Gene-based therapeutics has emerged as a promising approach for human cancer therapy. Among a variety of non-viral vectors, polymer vectors are particularly attractive due to their safety and multivalent groups on their surface. This study focuses on guanidinylated O-carboxymethyl chitosan(GOCMCS) along with poly-β-amino ester(PBAE) for si RNA delivery. Binding efficiency of PBAE/si RNA/GOCMCS nanoparticles were characterized by gel electrophoresis. The si RNA-loaded nanoparticles were found to be stable in the presence of RNase A, serum and BALF respectively. Fine particle fraction(FPF) which was determined by a two-stage impinger(TSI) was 57.8% ± 2.6%. The particle size and zeta potential of the nanoparticles were 153.8 ± 12.54 nm and + 12.2 ± 4.94 m V. In vitro cell transfection studies were carried out with A549 cells. The cellular uptake was significantly increased. When the cells were incubated with si Survivin-loaded nanoparticles, it could induce 26.83% ± 0.59% apoptosis of A549 cells and the gene silencing level of survivin expression in A549 cells were 30.93% ± 2.27%. The results suggested that PBAE/GOCMCS nanoparticle was a very promising gene delivery carrier.

关键词： Poly-β-amino ester Guanidinylated O-carboxymethyl chitosan Nanoparticles Gene delivery

A Modified KernelMethod for Solving Cauchy Problem of Two-Dimensional Heat Conduction Equation

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Advances in Applied Mathematics and Mechanics 2015年第1期7卷 31-42页

作者： Jingjun Zhao Songshu Liu Tao Liu department of Mathematics Harbin Institute of TechnologyHarbin 150001China

In this paper,a Cauchy problem of two-dimensional heat conduction equation is *** is a severely iⅡ-posed *** on the solution of Cauchy problem of two-dimensional heat conduction equation,we propose to solve this problem by modifying the kernel,which generates a well-posed *** estimates between the exact solution and the regularized solution are *** provide a numerical experiment to illustrate the main results.

关键词： iⅡ-posed problem Cauchy problem modified kernel method