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Experimental Study of Entropy Production in Cells under Alternating Electric Field

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Chinese Physics Letters 2012年第8期29卷 284-287页

作者： ding chang-Jiang LUO Liao-Fu Laboratory of Theoretical Biophysics School of Physical Science and TechnologyInner Mongolia UniversityHohhot 010021 College of Science Inner Mongolia University of TechnologyHohhot 010051

We put forward a new method for measuring the entropy production in the living *** involves heating the sample by alternating the electric field and recording the outward heat *** entropy production in a normal cell MCF10A and a cancerous cell MDA-MB-231 were measured and *** results show that the method is effective for the entropy measurement of a living *** scaled electro-induced entropy production rate(SEEP)of MDA-MB-231 monotonically increases with the electric field strength at 5–40 V/*** that of MCF10A changes non-monotonically and there exists a peak at 5–30 V/*** electro-induced entropy production ratio(EEPR)is smaller than 1 in a large range of field strengths,from 5 to 25 V/cm,which reveals that under 5–25 V/cm electric field exposure,the direction of the entropy flow may be changed from normal tissue to cancerous *** present a facile and effective strategy for experimentally investigating the thermodynamic properties of the cell and give a deeper insight into the physical difference between normal and cancerous cells under electric field exposure.

关键词： entropy Entropy recording

Recent advances of Pd-π-allyl zwitterions in cycloaddition reactions

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Chinese Chemical Letters 2023年第11期34卷 3-19页

作者： Juan Du Yun-Fan Li chang-Hua ding Guangxi Key Laboratory of Natural Polymer Chemistry and Physics College of Chemistry and MaterialsNanning Normal UniversityNanning 530001China Department of Chemistry Shanghai Engineering Research Center of Organ RepairInnovative Drug Research CenterShanghai UniversityShanghai 200444China

Palladium-catalyzed cycloaddition reactions via Pd-π-allyl zwitterions have been established as significant synthetic transformations to enable numerous carbon-or heterocycles compounds that are key constituents of various biologically active natural products and *** addition to the well-known Pd-π-allyl zwitterions,including palladium-trimethylenemethane and Pd-1,3/1,4-zwitterions,chemists have recently discovered new applications of several long ago reported but less-studied Pd-π-allyl zwitterions,which can straightforwardly and efficiently construct novel cyclic ***,some impressive newly designed zwitterions have been also *** zwitterions are diverse and can serve as transient and highly reactive intermediates for the subsequent cyclization with various *** this review,we highlight recent advances in applications of these two types of zwitterions in the synthesis of complex polycyclics and medium-sized cyclic compounds.

关键词： Palladium Cycloaddition Pd-π-allyl zwitterions Asymmetric catalysis Heterocycles

Input torque sensitivity to uncertain parameters in biped robot

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Acta Mechanica Sinica 2013年第3期29卷 452-461页

作者： chang-Tao ding Shi-Xi Yang Chun-Biao Gan Department of Mechanical Engineering Zhejiang University

Input torque is the main power to maintain bipedal walking of robot, and can be calculated from trajectory planning and dynamic modeling on biped robot. During bipedal walking, the input torque is usually required to be adjusted due to some uncertain parameters arising from objective or subjective factors in the dynamical model to maintain the pre-planned stable trajectory. Here, a planar 5-link biped robot is used as an illustrating example to investigate the effects of uncertain parameters on the input torques. Kine-matic equations of the biped robot are firstly established by the third-order spline curves based on the trajectory planning method, and the dynamic modeling is accomplished by taking both the certain and uncertain parameters into account. Next, several evaluation indices on input torques are intro-duced to perform sensitivity analysis of the input torque with respect to the uncertain parameters. Finally, based on the Monte Carlo simulation, the values of evaluation indices on input torques are presented, from which all the robot param-eters are classified into three categories, i.e., strongly sensi-tive, sensitive and almost insensitive parameters.

关键词： Biped robot · Uncertain parameter · Trajectory planning · Input torque · Sensitivity

Dynamical analysis and performance evaluation of a biped robot under multi-source random disturbances

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Acta Mechanica Sinica 2014年第6期30卷 983-994页

作者： Chun-Biao Gan chang-Tao ding Shi-Xi Yang The State Key Laboratory of Fluid Power Transmission and Control Department of Mechanical EngineeringZhejiang University

During bipedal walking,it is critical to detect and adjust the robot postures by feedback control to maintain its normal state amidst multi-source random disturbances arising from some unavoidable uncertain *** radical basis function（RBF）neural network model of a five-link biped robot is established,and two certain disturbances and a randomly uncertain disturbance are then mixed with the optimal torques in the network model to study the performance of the biped robot by several evaluation indices and a specific Poincar′e *** contrast with the simulations,the response varies as desired under optimal inputting while the output is fluctuating in the situation of disturbance *** results from noise inputting also show that the dynamics of the robot is less sensitive to the disturbance of knee joint input of the swing leg than those of the other three joints,the response errors of the biped will be increasing with higher disturbance levels,and especially there are larger output fluctuations in the knee and hip joints of the swing leg.

关键词： Biped robot Multi-source random disturbances Sensitive parameters RBF neural network Taguchi method Performance evaluation

Tetrahydrofuran Ring-opening with Acyloxyphosphonium Bromide Catalyzed by Zinc Bromide: An Effective Method for the Preparation of 4-Bromobutyl Esters

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Chinese Chemical Letters 2002年第7期13卷 589-592页

作者： Hua Yue WU Jin chang ding Shun WANG Department of Chemistry Wenzhou Normal CollegeWenzhou 325027

Catalyzed by zinc bromide, tetrahydrofuran ring can be opened with acyloxyphos- phonium bromide generated in situ to afford 4-bromobutyl esters under mild conditions in good to excellent yields.

关键词： Zinc bromide tetrahydrofuran ring acyloxyphosphonium bromide 4-bromobutyl esters.

Gallium trichloride-catalyzed conjugate addition of indole and pyrrole to α,β-unsaturated ketones in aqueous media

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Chinese Chemical Letters 2009年第6期20卷 676-679页

作者： Rong Xu Jin chang ding Xi An Chen Miao chang Liu Hua Yue Wu Wenzhou Vocational and Technical College Wenzhou 325035 PR China College of Chemistry and Materials Science Wenzhou University Wenzhou 325027 PR China

Michael addition of indole and pyrrole to a variety of α, β-unsaturated ketones was efficiently promoted by a catalytic amount of GaCl3 in aqueous media to afford the corresponding products in good to excellent yields.

关键词： Gallium trichloride Michael addition Indole Pyrrole α, β-Unsaturated ketones

An approach to the Paal–Knorr pyrroles synthesis in the presence of β-cyclodextrin in aqueous media

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Chinese Chemical Letters 2013年第9期24卷 793-796页

作者： Fu-Jun Duan Jin-chang ding Hong-Juan Deng ding-Ben Chen Jiu-Xi Chen Miao-chang Liu Hua-Yue Wu College of Chemistry and Materials Engineering Wenzhou University Wenzhou Vocational and Technical College College of Pharmaceutical and Chemical Engineering Taizhou University

An efficient and facile method for the synthesis of N-substituted pyrroles in moderate to good yields by the Paal-Knorr reaction of β-diketones with amines in the presence of β-cyclodextrin in aqueous media has been developed. Moreover, this process tolerated diamines （e.g., para-, metaor orthophenylenediamine） to construct bis-pyrrole or mono-pyrrole derivates.β-Cyclodextrin can be recovered easily after the reactions and reused without evident loss in activity.

关键词： Pyrrole Paal-Knorr β-Cyclodextrin Water

Molecular Characterization and Expression Analysis of TaZFP15, a C_2H_2-Type Zinc Finger Transcription Factor Gene in Wheat (Triticum aestivum L.)

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Journal of Integrative Agriculture 2012年第1期11卷 31-42页

作者： SUN Zhao-hua ding chang-huan LI Xiao-juan XIAO Kai College of Life Science Agricultural University ofHebei Baoding 071001 P.R.China College of Agronomy Agrieultural University of Hebei Baoding 071001 P.R. China

Based on sequencing of part clones in a root subtractive cDNA library, an expressed sequence tag （EST） sharing high similarity to a rice C2H2 zinc finger transcription factor （ZFP15） was obtained in wheat. Through bioinformatics approach, the wheat C2H2-type ZFP gene referred to TaZFP15 has been identified and characterized. As a full-length cDNA of 670 bp, TaZFP15 has an open reading frame of 408 bp and encodes a 135-aa polypeptide. TaZFP15 contains two C2H2 zinc finger domains and each one has a conserved motif QALGGH. The typical L-box, generally identified in the C2H2 type transcription factors, has also been found in TaZFP15. Phylogenetic analysis suggested that TaZFP15 shares high similarities with rice ZFP15 （GenBank accession no. AY286473）, maize ZFP （GenBank accession no. NM_001159094） and a subset of other zinc-finger transcription factor genes in plant species. The expression of TaZFP15 was up-regulated by starved-Pi stress, showing a pattern to be gradually elevated along with the progression of the Pi-stress in a 23-h treatment regime. Similarly, the transcripts of TaZFP15 in roots were also induced by nitrogen deficiency, and abiotic stresses of drought and salinity. No responses of TaZFP15 were detected in roots to nutrition deficiencies of P, Zn, and Ca, and the external treatment of abscisic acid （ABA）. TaZFP15 could be specifically amplified in genome A, B, and D, and without variability in the sequences, suggesting that TaZFP15 has multi-copies in the homologous hexaploid species. Transgenic analysis in tobacco revealed that up-regulation of TaZFP15 could significantly improve plant dry mass accumulation via increasing the plant phosphorus acquisition capacity under Pi-deficiency condition. The results suggested that TaZFP15 is involved in mediation of signal transductions of diverse external stresses.

关键词： Triticum aestivum L. zinc-finger transcription factor gene nutrition deficiency abiotic stress expression pattern

Hyperon Dynamics in Heavy-Ion Collisions near Threshold Energy

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Chinese Physics Letters 2021年第9期38卷 33-37页

作者： ding-chang Zhang Hui-Gan Cheng Zhao-Qing Feng School of Physics and Optoelectronic Technology South China University of TechnologyGuangzhou 510641China

Within the framework of quantum molecular dynamics transport model,the isospin and in-medium effects on the hyperon production in the reaction of ^(197)Au+^(197) Au are investigated thoroughly.A repulsive hyperon-nucleon potential from the chiral effective field theory is implemented into the model,which is related to the hyperon momentum and baryon *** correction on threshold energy of the elementary hyperon cross section is taken into *** is found that the𝛴yields are suppressed in the domain of midrapidity and kinetic energy spectra with the *** hyperons are emitted in the reaction plane because of the strangeness exchange reaction and reabsorption process in the nuclear ***∑^(−)/𝛴∑^(+)ratio depends on the stiffness of nuclear symmetry energy,in particular in the high-energy region(above 500 MeV).

关键词： potential density elementary